The bucardo, or Pyrenean ibex, lived high in the Pyrenees until its extinction in 2000. Three years later, researchers attempted to clone Celia, the last bucardo. The clone died minutes after birth. Taxidermic specimen, Regional Government of Aragon, Spain

Billions of passenger pigeons once filled the skies of eastern North America. Martha, the last one, died at the Cincinnati Zoo in 1914. Geneticists now think they could resurrect the species. Taxidermic specimen, Smithsonian Institution's National Museum of Natural History, Washington, D.C.

Though it looked like a wolf and was called a Tasmanian tiger, the thylacine was actually a marsupial — a relative of kangaroos and koalas. By the 1930s it had been hunted to extinction. Taxidermic specimen, American Museum of Natural History, New York

The bucardo, or Pyrenean ibex, lived high in the Pyrenees until its extinction in 2000. Three years later researchers attempted to clone Celia, the last bucardo. The clone died minutes after birth. Taxidermic specimen, Regional Government of Aragon, Spain

Saber-toothed cats went extinct after the ice age; paleontologists are not sure what caused their extinction. This cat was brought to life by a puppeteer: It's a creation of Jim Henson's Creature Shop. Body puppet, George C. Page Museum at the La Brea Tar Pits, Los Angeles

Saber-toothed cats went extinct after the ice age; paleontologists are not sure what caused their extinction. This cat was brought to life by a puppeteer: It's a creation of Jim Henson's Creature Shop. Body puppet, George C. Page Museum at the La Brea Tar Pits, Los Angeles

Sorry to disappoint, but science writer Carl Zimmer says we're not going to bring back dinosaurs. But, he says, "science has developed to the point where we can actually talk seriously about possibly bringing back more recently extinct species."

It's called "de-extinction" — and it's Zimmer's cover story for National Geographic's April issue.

In 2003, he tells Morning Edition's Steve Inskeep, scientists took some DNA that had been rescued from the very last bucardo, a type of wild goat that had recently gone extinct. And, long story short, they used a surrogate egg and mother to bring a bucardo — or something close to it — back to life. It was born with birth defects, lived for 10 minutes, and then went extinct again. But scientists saw this as a major breakthrough.

How de-extinction works is complicated, and that's what the National Geographic article is for. The bigger, arguably more pressing, question is: Why develop de-extinction? And there's a discussion about that on National Geographic's website, as well.

Ross MacPhee, a curator of mammalogy at the American Museum of Natural History in New York, is quoted in the magazine article as saying: "What we really need to think about is why we would want to do this in the first place, to actually bring back a species."

Leave your comments here, or join the discussion there. You can also follow what the leading scientists think, as they gather Friday for a daylong TEDx event in Washington, D.C. Or learn more in this TED talk by Stewart Brand, who heads up the Revive and Restore project.

Copyright 2013 NPR. To see more, visit http://www.npr.org/.

Transcript

STEVE INSKEEP, HOST:

Consider for a moment the premise behind the novel and movie "Jurassic Park." The notion in that movie - which came out 20 years ago - was that bits of dinosaur DNA could be used to grow new dinosaurs and bring back species from extinction. Reporter Carl Zimmer writes in National Geographic, that scientists are actually working on de-extinction, the real life resurrection of animals that have been lost in recent decades. He says it could happen soon for some animals, even if a T-Rex is unlikely to walk the earth again.

CARL ZIMMER: We're not going to bring back dinosaurs, because we can't get at their DNA but now we're at the point, 20 years later, where science has developed to the point where we can actually talk seriously about possibly bringing back more recently extinct species.

INSKEEP: What is the closest anybody has come to actually doing this?

ZIMMER: The closest anyone has come to doing this was 10 years ago. There was a species of mountain goat called the bucardo which lived in the Pyrenees Mountains between Spain and France.

INSKEEP: OK.

ZIMMER: And conservation biologists had been trying to save it for decades and it was just spiraling down. It had been over-hunted to the point where the species just couldn't go on.

INSKEEP: So just a handful of them left.

ZIMMER: And then finally the last bucardo died in 2000.

INSKEEP: A tree fell on it.

ZIMMER: That's right. A tree crashed down on this poor animal and it was dead, but before it had died they saved some cells from it. They had plucked a little tissue from its ear. And they got the DNA out of those cells and implanted eggs which they put into a surrogate mother, a hybrid goat ibex, and one of these surrogate mothers gave birth to a clone bucardo.

Unfortunately, it only lasted about 10 minutes. It had really serious birth defects. But that was the first time that any species had come back from extinction.

INSKEEP: It lived.

ZIMMER: It was alive.

INSKEEP: So they got close but that's the closest anyone has come and that's like a decade ago, was it not?

ZIMMER: Mm-hmm.

INSKEEP: So what makes you think that the moment has truly, truly arrived?

ZIMMER: Two reasons. One reason is that cloning has gotten much better as a technique. So scientists know how to get animals cloned efficiently, and to make sure that they're healthy when they're born. Not only that but, you know, scientists can work with material that before would have been thought to be too degraded.

So there's a project going on now, through a non-profit called Revive and Restore - in collaboration with scientists at Harvard - where they're looking at reviving the passenger pigeon. Now, the thing is that there are no viable cells of passenger pigeon left. They've been dead for a century. And so all you have are these museum specimens. But they have fragments of DNA.

So what you can do is you can figure out what the sequence of the passenger pigeon genome is, and then you can synthesize little chunks of its DNA and then paste them in to the DNA of a living pigeon.

INSKEEP: But as scientists go forward with this, what are the ethical problems that are raised?

ZIMMER: Well, some people might feel that, you know, this is wrong because, oh, we're playing God. And I think that that's kind of a dubious argument, because in a lot of cases we drove these species extinct. So that, I think, we can set aside. I think a deeper, more important question is, is this actually a good use of resources to deal with what is an ongoing extinction crisis.

INSKEEP: Mm-hmm.

ZIMMER: What is happening now is, not just business as usual. We are dealing with an extinction crisis primarily of our own doing through pollution, through climate change, through all these different factors.

INSKEEP: Carl Zimmer wrote an article in National Geographic about efforts to take animals that were extinct and bring them back to life. Thanks very much.

ZIMMER: Thank you.

INSKEEP: Oh, now this is cool. National Geographic hired a photographer who used a nearly extinct photo technique to capture images of actually extinct species. You can see those images at NPR.org. Transcript provided by NPR, Copyright NPR.